BOLD-fMRI基于体素镜像同伦连接方法分析高原缺氧对高原正常人群脑功能的影响

Analysis of plateau hypoxia on brain function in normal population by resting-state BOLD-fMRI voxel-mirrored homotopic connectivity

目的:采用BOLD-fMRI技术分析高原缺氧环境对正常人脑功能连接的影响,并从影像学角度分析其生理机制。方法:收集世居高原健康藏族大一学生(实验组)及初入高原2个月内健康大一汉族志愿者(对照组)各30例,采用BOLD-fMRI技术分析2组基于体素的镜像同伦连接(VMHC)的差异。结果:静息态下对照组相对于实验组大脑半球间VMHC呈局部对称性增强,表明额部脑区两侧功能连接增强,差异有统计学意义(P<0.001,Cluster>5,TFCE校正)。2组VMHC值与简易智力状态检查量表评分无相关性(r=0.04,0.29;均P>0.05)。结论:高原低压、低氧环境影响大脑半球间功能连接模式,可能是初入高原发生轻度高原反应及大脑适应性变化的生理机制之一。

Objective:To study the plateau hypoxia on brain function in normal population and its physiological mechanism by resting-state BOLD-fMRI. Methods:Thirty healthy Tibetan freshmen who lived on plateau for generations were collected as experimental group,and thirty healthy Han freshmen who lived on plateau for two months were collected as control group. Analysis of difference of voxel-mirrored homotopic connectivity (VMHC) between the two groups by resting-state BOLD-fMRI was analyzed. Results:Compared with experimental group,interhemispheric VMHV of control group showed a phenomenon of local symmetry enhancement,which indicated the functional connections on both sides of the frontal brain area were enhanced,and the difference was statistically significant (P<0.001,Cluster>5,TFCE correction). And there were no differences of VMCH value and MMSE score between the two groups(r=0.04,0.29;both P>0.05). Conclusions:The plateau low-pressure and hypoxic environment affects the functional connection mode between the cerebral hemispheres,which may be one of the physiological mechanisms of mild altitude sickness and brain adaptive changes in the first entry in plateau.